I recently watched Bong Joon-Ho's Snowpiercer and it got me thinking of Elysium. Both are heavy-handed sci-fi allegories --ie, the best kind -- and both construct worlds that barely make a lick of sense.
I loved Snowpiercer. I mostly enjoyed Elysium, but I kept wanting to rewrite it so it made more sense. For example, I'd set it much farther in the future, with more shorty toga-wearing characters, fewer overt references to the present-day world, and a greater sense that virtually no one understands the systems running their society anymore, and thus can be reprogrammed by a single important guy.
All of that would make the story easier to swallow. Even the magi-tech medical beds.
Snowpiercer takes place barely 20 or 30 years in the future, in a totally transmographied 'society' aboard one of least believable 'arks' in SF history. And yet, I bought the whole thing hook, line, and sinker.
It comes down to tone, I think. But I can't quite articulate why the tone fails the story badly in Elysium.